“He’s spent so much time in Iowa, he has friends all over this state,” Sen. Tom Harkin, D-Iowa, said before Biden headlined Harkin's annual steak fry. “I’m pretty sure he’s an Iowan at heart, and one of the few people outside this state who can honestly say he’s been to every one of our 99 counties more than once.”

Should Biden run for president in 2016, as his recent trip to Iowa suggests he is considering, he will likely lean heavily on his vast, impressive collection of friends in Iowa, a group that includes former and current Democratic lawmakers, political operatives, interest group leaders and activists.

Biden has curated his Iowa network since 1974, when he paid his first political visit to the state for the first-in-the-nation presidential caucuses to stump for former Sen. John Culver. In 1987, Biden was back, nurturing and expanding those connections as a candidate for president. In 2007, Biden picked up where he left off in Iowa and ran for president again.

In between, Biden has spoken regularly at Harkin’s steak fry and attended myriad other Democratic Party functions large and small.

Sharon Holle, of Davenport, Iowa, met Biden at a dinner in 2007, just as Biden was gearing up for his second presidential campaign. She ferried him around the room and introduced him to the requisite party players. By the end of the night, Biden said to her, “You’re a keeper!” He meant it, and he returned the next week to personally hire Holle to lead his Davenport office.

“He remembers things about you. It’s just amazing,” said Holle, who has been a fan of Biden since his first presidential bid in 1987. “In a crowd, you’ll see him, and he’ll say, ‘How’s your son doing?’ or ‘How’s your store coming along?’ He’s got this amazing memory, and he can remember a face and a story. He makes you feel like you’re a friend.”

When he travels in Iowa, Biden on occasion forgoes hotels to stay with some of those friends. He is said to have a particularly strong network in northeast Iowa, anchored in Dubuque.

“It was cultivated as far back as '88, and those '88 folks were still with him last time,” said Pete D’Alessandro, an Iowa-based political consultant. “When he ran that very first race years ago, he really resonated with folks up there.”

But there are glaring limits to Biden’s relationships.

In 2008, Biden received less than 1 percent of the Iowa caucus's vote, trailing Democrats Hillary Clinton, Barack Obama and former Sen. John Edwards.

Clinton established her own extensive network in Iowa during that campaign — one that could counter Biden's should they both mount presidential bids again in 2016.

“They’re similar in that there’s a core group of folks out there who are fiercely loyal to Clinton and a group of folks who are fiercely loyal to Biden,” said Iowa Democratic Party Executive Director Troy Price.

Committed Biden supporters in Iowa think the vice president’s stock has risen over the last eight years, however, making him a more formidable contender should he seek the presidency again.

If he does, Biden will know how to activate old relationships in Iowa and, critically, forge new ones. He's had years of practice.

Jeff Smith, who worked in Iowa as deputy political director for former Sen. Bill Bradley's 2000 presidential bid, remembers meeting Biden on Capitol Hill in 2001 — and, upon mentioning his Iowa credentials, being ushered into Biden’s office for a nearly two-hour meeting.

Biden, who was weighing a 2004 presidential bid, quizzed Smith about his Iowa connections and rattled off his own as he mapped out the potential Democratic field. If Clinton ran, it’d be hers to lose, Biden reasoned, but he doubted she would jump in.

“I’m perfectly happy in the Senate. I don’t need to be president,” Biden told Smith. “But we gotta have somebody who can win next time. Somebody who can relate to regular people.”

Biden urged Smith to keep in touch before adding, “We’re gonna need your help if we do this.”